If all you know about Shabana Mahmood’s interview with the comedian Matt Forde, which was recorded live at a West End theatre on Monday, is that she said a heckler should “fuck right off”, then it’s worth listening to the heckle itself. Hell, knock yourself out and listen to the whole podcast. The accompanying blurb calls the home secretary “impassioned, thoughtful and hilarious”, which we’ll come back to, except to say there is nothing hilarious about this exchange.

The heckler accused Mahmood of “out-Reforming Reform” and confecting a “theatre of cruelty” with her new immigration policy ideas, before being removed by security.

In a nutshell, Mahmood has doubled the length of time required to get settled status (to 10 years) and refugees will now have their status reviewed every 30 months. We could split hairs over whether this out-Reforms Reform or merely apes them, but either way the position seems vindictive. Even those who like these policies would not have expected a vote for the Labour party to deliver them.

Profanity in politics, once completely out of bounds, lands differently now – one researcher at Cardiff analysed Donald Trump’s dropping of an F-bomb while talking about Iran and Israel in June last year and concluded that it made him sound relatable, solidified his reputation for straight talking, would probably not alter voting intention even among those who deplored it and, crucially, didn’t sound as shocking as it once would have. Swear words don’t connote violent contempt any more; not when we all use them, all the time.

This was not a John Prescott moment (for younger readers, this involved the then deputy prime minister punching a guy who had thrown an egg at him). Mahmood didn’t shoot from the hip and address the heckler head on – she waited until he’d been removed to discuss the incident with Forde. The tone is of a politician not even trying to sound tough via the use of expletives, but rather cool and fun. You can hear the comedian egging her on with encouraging guffaws while she basks in the approval. The dominant mood – self-loving chumminess – we have probably all indulged in, but that doesn’t make it relatable.

Then she goes on the offensive, and calls this “just a way of delegitimising the point of view that I bring to the table”. That slightly therapised word is the language of victimhood: disagreement happens between equals; delegitimisation is what the powerful do to the weak. It is an objectively absurd framing from the home secretary – the only person who could strip her of her public legitimacy is the prime minister himself – but a very familiar rightwing bait and switch, in which you parade power and dominance only to cry victim once you’re challenged on it.

Mahmood’s next argument followed another familiar route, projecting her own victimhood on to the “valid, legitimate views of millions of people in this country”, as if by disagreeing with her, you marginalise all your unnamed, innumerable compatriots. Again, ridiculous: she’s a home secretary, making an argument. She has no particular claim to channel the feelings of the masses.

Mahmood goes on to say of the hecklers, “you’re trying to put me in a box, which includes a lot of people who think I don’t even belong in my own country”. As grammatically baffling as this is, she does make her fundamental opinion plain. “That’s why I said this individual can just fuck right off, because I know I belong in my own country. You’re not going to be able to do that to me,” she concludes, dismissing those arguing with her as “white liberals”. (Green New Deal Rising, which organised the disruption, has said that the heckler was a person of colour.) It’s not so much senseless as deeply cynical. Most of those opposing Mahmood’s immigration plans aren’t doing it because they don’t think she belongs in the UK, and she knows that.

When the home secretary prioritises the “legitimate concerns” of Reform supporters over the values of her own party, we can, and do, argue for ever about electoral calculus, realism, will to power – all staple wedge issues for Labour. But in this episode, her contempt for the values of her own party appears to be quite naked. So maybe that expletive is seismic after all: she has restored its power to shock.

• Zoe Williams is a Guardian columnist

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